Closed loop information path for medical fluid delivery systems

ABSTRACT

This invention relates generally to the field of medical devices for delivering medicinal fluids to patients during medical procedures and more particularly, this invention relates to improved medical fluid delivery systems and methods of use which incorporate a closed loop information path from the manufacturer to a product user such as a hospital or other medical institution and back to the original manufacturer. The information originally incorporated with the product is used by the consumer to aid in use of the product. The information which accompanies the product is updated and new information is added in order to provide the manufacturer with information on how the product is used.

This is a continuation application of Ser. No. 08/273,665 filed on Jul.12, 1994, now abandoned.

This invention relates generally to the field of medical devices fordelivering medicinal fluids to patients during medical diagnosticprocedures and more particularly, this invention relates to improvedmedical fluid delivery systems and methods of use which incorporate aclosed loop information path from the vendor to a product user such as ahospital or other medical institution and back to the original vendor orits representative. The information originally incorporated with theproduct is used by the consumer to aid in use of the product. Theinformation which accompanies the product is updated and new informationis added in order to provide the vendor with information on how theproduct is used.

DESCRIPTION OF THE RELATED ART

It has been recognized that the inclusion of machine readableidentification codes on a product can increase the utility, reliabilityand efficiency of the product by allowing the product to be more readilyand accurately incorporated into a system which uses the product. Theinclusion of these codes primarily eliminates the potential forintroducing operator error by removing the need for the system operatorto enter various product information which alters operation of thesystem. Additionally, these systems save time by reducing or eliminatingthe time it takes for the information to be entered into the system.These systems are extremely useful in the medical field where accuracyis critical and failure to properly use a system can have devastating oreven fatal consequences.

Conventional medical fluid delivery systems have not used machinereadable codes beyond bar codes used for inventory information,primarily because the systems of the prior art were not sufficientlyversatile to make such systems useful. Conventional medical fluiddelivery systems generally used a single disposable source of contrastmedia. In these systems, a doctor would select a concentration ofcontrast media and injection rate based primarily on the study to bedone, with consideration of the size and weight of the patient as wellas other additional factors. This fixed set of injection parameters isconsidered to be a standard delivery protocol. Once the doctor selectedthese parameters, the entire bottle of contrast media was used for thatpatient. There simply was no need for these systems to read and react toinformation relating to the contents of the fluid container because theentire container was completely injected or discarded, and the systemsdid not operate differently for different types and concentrations ofcontrast media.

Although it has been recognized that varied dosing requirements forpatients exist in medical imaging procedures, conventional medicalimaging procedures continue to use pre-set doses or standard protocolsfor injecting contrast media during medical imaging procedures. Standardprotocols have been used primarily to minimize the potential for errorsand decrease the likelihood of having to repeat the procedure, anoccurrence which requires that the patient be exposed to additionalradiation and contrast media. As noted, in prior art contrast deliverysystems, once a bottle of contrast media was opened for use on a patientit could not be used on another patient primarily due to contaminationconsiderations. Existing contrast delivery systems do not prevent thesource of contrast media used for an injection from being contaminatedwith body fluids of the patient.

Some of the shortcomings of existing imaging systems and procedures havebeen addressed and resolved in co-pending application Ser. No.08/144,462 filed October 1993, titled "Total System For ContrastDelivery," and Ser. No. 08/309,820, titled "Patient Specific DosingContrast Delivery Systems and Methods," filed Sep. 21, 1994. Eachapplication is incorporated herein by reference.

These applications disclose a contrast media delivery system whichprovides a source of contrast media which is sufficiently isolated froma patient undergoing an imaging procedure that the source of contrastmedia may be used on additional patients without concern forcontamination. The system incorporates a source of contrast media, and,if desired, a diluent. Each is sufficiently isolated from the patient toprevent contamination. The contrast preferably has a concentration whichis the highest that would be used in an injection procedure so that theoperator may combine the contrast media with a diluent and select thedesired concentration of contrast media for any given procedure.

These improvements in the field of medical imaging systems present theneed for a system which incorporates the ability to automatically readinformation from a source of contrast media which identifies at the veryleast, the amount and concentration of the source of contrast media.This is necessary so that the system may automatically adjust themixture of contrast media and diluent for a desired concentration ofcontrast media. Furthermore, because the systems disclosed in theabove-referenced co-pending applications are designed for use with morethan one patient, the system must also be aware of the initial volume offluid so that the system is able to automatically warn the operator whenthe supply of fluid is less than the amount necessary to complete agiven imaging procedure. There is also a need to incorporate otheruseful information such as, for example expiration date of the materialand information related to calibration of the device etc.

A fluid delivery system which incorporates the use of machine readablecodes associated with a fluid container used in the system would be muchmore useful and versatile if the system was also capable of updating thecodes or adding additional information to the record member whichcontains the original codes. The updated information could be usedduring future procedures, such as, for example, by noting the amount ofcontrast media which has previously been used from a given source sothat the system may warn an operator when there is insufficient fluid tocomplete a given procedure. New information could also be added to therecord member which is useful for the original vendor such asinformation relating to how the system is actually used. Suchinformation could also be used for billing of the customer, the patient,or for determining royalty payments. This is especially useful insystems which are reused or recycled because these devices are alreadyreturned to the vendor where this information could readily beextracted. Alternatively, the information could be electronicallytransmitted to the vendor if the fluid containers are not returned.

Accordingly, it is an object of the present invention to provide animproved fluid delivery system which incorporates the use of machinereadable codes on the fluid containers for the system to read and usefor calculating injection parameters.

It is a further object of the present invention to provide a fluiddelivery system which is capable of updating and adding new informationto the machine readable codes used by the system.

It is another object of the present invention to provide a closed loopinformation path which sends information from the manufacturer to aproduct user and back to the manufacturer or its representative usingelectronic transmission or machine writable/readable codes.

Numerous other objects and advantages of the present invention willbecome apparent from the following summary, drawings and detaileddescription of the invention and its preferred embodiment.

SUMMARY OF THE INVENTION

The invention includes apparatus and methods for storing machinereadable and writable/readable codes on a record member whichaccompanies a medical fluid container for use in diagnostic medicalimaging procedures or other medical fluid delivery systems. In apreferred embodiment, a medical fluid container is disclosed whichcontains machine readable codes located in a record member or memorydevice which accompanies the medical fluid container. The memory unit orrecord member, if electronic, incorporates its own power supply, ifneeded, so that its operation is independent from the system andinformation stored on the device will not be lost when the container isremoved from the fluid delivery system.

The memory device in a preferred embodiment is partially encoded by themanufacturer although this is not necessary if information from thevendor is not required for system operation. An example of this would bewhen a vendor is only interested in determining the amount of fluidreturned from a product user. In this situation, when the fluidcontainer is returned to the vendor, the memory would containinformation on the amount of fluid used so that the vendor could creditthe consumer for the unused portion of the material.

In other interactive systems, the information typically encoded by themanufacturer would include information defining the amount of fluid inthe container as well as the type and concentration of the fluid. Whenthe fluid container of the present invention is attached to a medicalfluid delivery system, the memory device is also connected to thesystem. The electronic control system (ECS) is able to read and downloadinformation into the system memory of the injection system. Disablecircuitry is also incorporated into the fluid delivery system to preventthe fluid delivery system from operating without the proper connectionof the memory device.

Other information is also incorporated by the vendor for use by thesystem such as the size of the fluid path elements which form theconnection between the fluid containers and the patient. This is usefulduring calibration of the machine. Additionally, pressure rating of thefluid path could be incorporated to prevent the system from exceedingthese limits inadvertently. This capability makes the system moreflexible because it is able to use various components beyond thoseconsidered by the original designers. For example, tubing sizeinformation could be utilized for automated tubing filling to remove airfrom the lines after installation of the fluid path but beforeconnection to a patient.

The memory device disclosed in the preferred embodiment is awritable/readable unit which incorporates its own independent powersupply for sustaining information entered into its memory.Alternatively, it is contemplated that the system would employ anencoded magnetic strip which could also be updated. The system istherefore particularly useful in systems which are returned to a vendorfor reuse or recycling. The system is able to provide a simple andeconomical means for the vendor to receive information on the use of itsproduct. The control system automatically stores information related tothe consumer's use of the system in the chip or chips which make up thememory unit or alternatively, the magnetic memory may be updated.

The memory unit would act as a "flight recorder" for the system andwould store information related to the number of patients served by thefluid container, the actual concentration of contrast media used by thesystem and the flow rate of the injection etc. This information wouldenable manufacturers to improve service by providing them with up todate knowledge about actual use of their systems.

Other devices are disclosed which employ various types of read onlyencoding to increase the utility and efficiency of multi-patientcontrast media injection systems as well as other medical fluid deliverysystems. These systems primarily rely on the use of read only codes tosupply information to the system which eliminates the potential foroperator error while speeding up the procedure. These read only codesare typically bar codes or metal codes such as those used on filmcontainers. Other interchangeable alternatives include optically sensedcodes which are sensed via a CCD or equivalent device or physicalsurface codes detected by mechanical switches.

It is contemplated that the systems which rely on a read only device forthe transfer of information also incorporate the ability to update theinitial information or provide new information such as, for example, byprinting new bar codes or otherwise altering the initial information.

Specific examples of these contemplated alternative designs areprimarily directed to calibration of medical fluid delivery systemswhere it is necessary to receive information related to variousoperational parameters such as tubing size and pressure limits for safeoperation of these systems. Incorporation of machine readable codeswould enable the system to automatically calibrate, set pressure limitsor verify whether correct parts are connected to the machinery. Thesesystems may employ bar coding so that the operator may automaticallyinput various operational parameters into the system via a bar codereader. The system would then perform various calculations to assuresafe operation.

The bar codes may be found in association with the various parts of thesystem which form the fluid flow path so that the system is able tooperate with a wide variety of these devices thereby increasing theoverall versatility of the fluid delivery system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of a medical fluid delivery system whichincorporates the present invention.

FIG. 2 is a flow diagram outlining use of the closed loop informationpath.

DESCRIPTION OF THE INVENTION AND ITS PREFERRED EMBODIMENT

FIG. 1 illustrates various stages of a system shown generally at 10which incorporates the memory device of the present invention. Thepreferred embodiment incorporates a writable/readable memory devicewhich is capable of sending and receiving information from a medicalfluid delivery system. There are various memory devices which can beused in such a system, such as, for example, the DS14941-5f manufacturedby Dallas Semiconductor of Dallas, Tex., or the Datakey manufactured byDatakey of Burnsville, Minn.

These chips can be packaged in a 16 mm Micro Can or incorporated into aninsertable key-like device. The Dallas Semiconductor device incorporatesits own power supply so that the contents of the memory will besustained without an external supply of power. These devices havegreater than 10 years of built in power which is more than sufficientfor use with the present invention.

In the example of the preferred embodiment, a medical fluid vendor 12,produces a coded fluid delivery module 14 with an associated codedmemory unit 16. The fluid delivery module 14 is a unit whichincorporates various fluid delivery elements such as the fluid containeror containers and associated tubing for making various connections tothe fluid delivery system. These are preferably pre-connected andsterilized, but may also come as separate pieces which an operator mustconnect. The memory unit 16, which is considered to be associated withthe various fluid delivery elements when it is associated with the fluiddelivery module 14, may also be individually associated with one or withseveral of the fluid delivery elements.

The medical fluid vendor encodes information necessary for properoperation of a medical fluid delivery system 18. The fluid deliverysystem 18 incorporates the fluid delivery module 14 as shown in FIG. 1.Information is encoded and incorporated with the delivery module whenthe vendor packages the medical fluid delivery module for distribution.This information includes data related to the type, concentration andvolume of the fluid in the container which accompanies the memorydevice. Other information which may be stored by the fluid vendorincludes information related to calibration of the system such as theinside diameter, length and total volume of the tubing which accompaniesthe fluid delivery module to form the connection between the containerand the injection system. Inside diameter is important if the tubing ispart of a peristaltic pump. The inside diameter determines thecalibration of the pump in milliliters/revolution. Inside diameter andlength or total volume are used if the system will automatically purgeair from the tubing. Information related to such variables as tubingpressure rating, expiration date of the material from which the tubingis made, or expiration date of the medical fluid may also be encoded.Certain memory locations would contain a system enable code to verifyproper installation and reading of the coded fluid delivery module.

Information which is encoded and stored on the memory device is thusable to set operating parameters for the system. Operating parametersfor the system include any data which is used in association with theoperation of the system such as, for example, the calibration data andset up data noted above as well as data related to fluid characteristicssuch as type, concentration, manufacturer, expiration date and volume offluid in the fluid container.

When a system operator installs the coded fluid delivery module 14 tothe medical fluid delivery system 18 an electrical connection is madebetween the memory device and the fluid delivery system. With the Dallasdevice, the can may be mounted on the side of a fluid delivery moduleand spring contacts on the durable part of the delivery system would becontacted when the fluid path is properly in place. Alternatively, theData key device could be attached to the fluid delivery module or any ofits associated elements such as, for example, the fluid container,tubing or packaging by a lanyard. It would then be inserted into asocket on the durable equipment by the operator.

The Electronic Control System (ECS) 19 of the fluid delivery systemcommunicates with the memory device 16 and downloads that informationstored by the vendor which is necessary for use by the ECS incontrolling the fluid delivery system. The ECS 19 controls the variouselements of the fluid delivery system, such as the metering pumps, thepressurizing pump and heaters. These elements and others are describedin more detail in the aforementioned co-pending applications.

In alternative embodiments which employ read only coding, such as, forexample, bar codes, metal codes, optical sensing, mechanical codes, orpatterned magnetic ink, the coding also includes enable codes to assurethe proper reading of the coded information. The metal codes employ theuse of decipherable current and resistance paths to transfer the codedinformation such as those used in cameras. The optical sensingcapability refers to the use of CCD's to decipher coded information.

Once the fluid delivery system 18 receives the coded information, thesystem parameters are adjusted accordingly. The automatic reading ofthis information saves time and reduces the chances for operator errorby eliminating the need for the operator to enter this systeminformation.

Regardless of the embodiment, a successful read of the informationenables the system for use during a given medical procedure. Anyinformation necessary for instituting the injection is now contained inthe memory of the of the ECS.

In a preferred embodiment, the fluid delivery system 18 may update thecoded memory unit 16 either during and/or after completion of themedical procedure. This is accomplished by writing information to thecoded memory unit 16. Totally new information may be added and existinginformation may be removed and updated. When using an electronic device,it is useful to read after writing to verify proper writing. The usedfluid delivery module 14' is then returned to the vendor for informationextraction and reuse or recycling.

In devices which incorporate read only type memory units the informationmay be updated by generating new codes, such as, for example, includinga system which can generate and print new bar codes base on systemgenerated information. The newly printed bar code is then placed on theunit which is returned to the vendor. It will be appreciated that it isnot necessary for the vendor to include initial information in the codeddevice and that the coded device may be used for the return ofinformation only. Alternatively, information may be received by thesystem only and not updated for return to the vendor. This isparticularly true of calibration or set-up information for medical fluiddelivery systems.

Set-up information refers generally to information which is used to setpressure limits and identify the total volume of the fluid deliverypath. Calibration data refers generally to information used to setparameters for use of a pumping mechanism such as, for example, aperistaltic pump. Preparation of the fluid delivery system for useincludes using the calibration and/or set-up data to set various systemoperating parameters.

In FIG. 2, the numeral 20 identifies a flow diagram according to thepresent invention. Information is stored in a memory unit whichaccompanies a product at a vendor site in initial step 22. The productis then delivered to a consumer which incorporates the product into alarger system at step 24. The stored information is used by the systemin step 26 and new information relating to use of the product is thenstored in step 28. The product is returned to the vendor in step 30where the information relating to use of the product is received by thevendor. The system is particularly useful with reusable/recyclableproducts which in many instances are already returned to the vendor.

If the products do not need to be recycled, the information could berecovered by the vendor via electronic means, such as telephone orradio. This would be especially useful if billing is based upon thisinformation. This is an alternate closed loop information path althougha portion of the path relies on electronic transmission.

While the telephone or radio link is quick, it does require additionalhardware cost. For very expensive machines, such as high end copiers byXerox, telephone reporting is presently done. An advantage of thepreferred embodiment of returning the information with the fluid pathmodule is that no significant additional hardware is needed. Thehardware needed to read the information from the electronic recordmember is sufficient to write to it.

Information is recovered periodically or shortly after a container isreplaced. The recovered information includes some of the information thevendor initially stored with the fluid container as well as any newinformation added at the consumer site. Some of the recoveredinformation, if desired, specifically identifies the particular fluiddelivery module or memory unit by a unique serial number or referencecode. The Dallas Semiconductor device has a portion of its memorydedicated for this purpose. The recovered information is useful inproduct tracking and potentially automatic re-ordering, to save customertime and reduce inventory costs. The recovered information may betailored to individual vendor needs to assist in marketing efforts andincreasing vendor knowledge about the use of their products. A widevariety of information could be stored and retrieved in this manner. Thefollowing table provides examples of information which would be storedand retrieved by the system:

Sample Table of Information

Per Fluid Module or Container:

A) Timestamp (Date and Time) of installation into the fluid deliverysystem.

B) Timestamp of removal from the system.

C) Number of injections.

D) Machine Identification Code.

E) Information on machine status.

F) Error codes, if any.

G) Contrast remaining, if any.

Per Usage

1) Timestamp of injection.

2) Concentration used, if able to dilute.

3) Total volume.

4) Flowrates and durations.

if patient specific information is used, then:

5) Procedure information.

6) Patient information (not identifying the patient)

Sample Uses for Information

(A) and (B) can be combined with information on shipping time to a userto determine how many containers should be kept in inventory to meetdemand but minimize the amount of inventory.

(C) and (D) accumulated by the vendor over time can help the vendor'sservice people determine when to perform preventative maintenance.

(E) and (F) can be used by the service people as well.

(A) compared with the expiration date can be used to makerecommendations on inventory amounts or rotation procedure.

(G) compared to initial fill can be used if the billing of the customeris done on a per fluid volume basis rather than fixed price, or if thereis a rebate for fluid returned unused.

The equipment could be provided on a lease basis, with the returnedinformation (C) being used for customer billing.

(A), (B), (C) and the per injection information can be provided to thelocal salesman who may recommend that a different container size beused; smaller if (B)-(A) is near the limit for sterility time in themachine; larger is (B)-(A) is so short that the hassle of installing newcontainers is significant.

If a variable number of disposables come preattached, (C) can be used torecommend to the customer that he should have more or less disposablesets attached. More sets could save him money because he could use allthe fluid more often. Fewer sets would save a little by having less tothrow away.

The salesman can also use the per injection information to help one userachieve additional savings by sharing information about how other usersuse the system, such as protocols for various procedures.

The combined information of (A), (B) and (C) from many sites can be usedfor the vendor's production planning and strategic planning. This helpsa vendor not be fooled by buying patterns which are influenced byyear-end budgets, because the vendor has actual usage information.

Although the present invention has been described in terms of preferredembodiments, the present description is given by way of example only andis not intended to be limiting to the scope of the invention describedand claimed herein.

I claim:
 1. A method of storing information on and retrievinginformation from a record member in association with a medical fluiddelivery element comprising the steps of:a) storing information on therecord member at a vendor site; b) retrieving the stored information ata consumer site; c) calculating parameters for operation of a medicalfluid delivery system which incorporates the medical fluid deliveryelement based on the retrieved information; d) storing new informationon the record member at the consumer site; and e) retrieving the newinformation at the vendor site.
 2. The method of storing and retrievinginformation of claim 1, further comprising the step of providing areadable/writable electronic device as the record member.
 3. The methodaccording to claim 2, wherein a magnetic strip is provided as the recordmember.
 4. The method according to claim 1, wherein the retrievedinformation is used in billing the consumer site.
 5. The methodaccording to claim 1, wherein new information is added at the vendorsite for reuse of the product.
 6. A method of storing information on andretrieving information from a medical fluid delivery module comprisingthe steps of:a) storing information on the fluid delivery module at avendor site; b) retrieving the stored information at a consumer site; c)calculating parameters for operation of a medical fluid delivery systemwhich incorporates the medical fluid delivery module based on theretrieved information; d) storing new information on the fluid deliverymodule at the consumer site; and e) retrieving the new information atthe vendor site.
 7. The method according to claim 6, wherein theinformation is stored with a machine readable bar code.